US5310599A - Method for making polymers of alpha-hydroxy acids - Google Patents
Method for making polymers of alpha-hydroxy acids Download PDFInfo
- Publication number
- US5310599A US5310599A US08/057,817 US5781793A US5310599A US 5310599 A US5310599 A US 5310599A US 5781793 A US5781793 A US 5781793A US 5310599 A US5310599 A US 5310599A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/06—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from hydroxycarboxylic acids
- C08G63/08—Lactones or lactides
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
- C08G63/82—Preparation processes characterised by the catalyst used
- C08G63/823—Preparation processes characterised by the catalyst used for the preparation of polylactones or polylactides
Definitions
- the present invention is directed to a method for making polymers of alpha-hydroxy acids.
- it is directed to a method for making such polymers by catalyzed ring opening of the cyclic esters of certain alpha-hydroxy acids.
- biodegradable polymers Because of the increasing problem of disposing of industrial and domestic wastes, there is currently substantial interest in the use of biodegradable polymers in many applications. Among the more serious of these problems is the disposal of various plastic wastes, containing polymers such as polyethylene, polypropylene, polystyrene, polyurethanes and the like. These by and large are not biodegradable, particularly after being covered, such as in a landfill. Though polymers of lactic acid and glycolic acid and several other aliphatic polyesters are known to be hydro/biodegradable (i.e., they are readily degradable through the action of water and/or microorganisms.), their widespread use has been hindered by their high cost of production. The manufacture of alpha hydroxy acid polymers and copolymers has been costly in large part because of the difficult process by which they have been made heretofore.
- lactide (3,6-dimethyl-1,4-dioxane-2,5-dione) and glycolide (1,4-dioxane-2,5-dione) which are composed of two units of lactic or glycolic acid in the form of a ring, respectively
- a ring opening catalyst such as stannous octoate, or a compound of yttrium or a lanthanum series rare earth catalyst or a titanate.
- German application DE 3936188A1 describes the use of a screw extruder for polymerization of lactide, glycolide and mixtures thereof.
- U.S. Pat. No. 4,033,938 to Augurt et al. is directed to the polymerization and copolymerization of substituted 1,4-dioxane-2,5diones to produce polymers which readily absorbed in mammalian tissue. Copolymers of such diones with glycolide and lactide are disclosed using a stannous chloride catalyst. Copolymerizations with lactides are shown to require a minimum time of 2 hours at 180 C.
- U.S. Pat. No. 4,644,038, Protzman is directed to copolymers of poly (alpha-hydroxy acid) and ethylenically unsaturated epoxides which are prepared by copolymerization of C2-5 alpha hydroxy acid diesters with ethylenically epoxides in the presence of both a ring opening catalyst and a free radical initiator.
- Various ring opening catalysts are disclosed such as stannous octoate, tin chloride, diethyl zinc and zinc chloride. The time to effect copolymerization was greater than one hour at 175 C.
- the drawing consists of a single FIGURE which is a graphical correlation of the effect of organic acid on the rate of lactide polymerization.
- the invention is therefore directed to the problem of improving the rates of the polymerization of lactides and glycolides to such an extent that they can now be carried out economically in commercial scale quantities.
- the invention is therefore directed to an improved method for preparing polymers of alpha-hydroxy acids by catalyzed ring opening of cyclic esters of the alpha-hydroxy acids comprising the sequential steps of
- the present invention is a method for increasing the rate of polymerization in a catalyzed ring opening polymerization for producing glycolide based polymers, lactide based polymers, copolymers thereof or copolymers of either with up to 20 weight percent of one of the herein below defined comonomers.
- An essential element of the present invention is that mol ratio of acid impurity to catalyst present in the reaction medium be maintained below 6:1; and preferably below 1:1. Because any water present can cause ring scission of the lactide or glycolide, it is considered as acid for purposes of the present invention.
- the polymerization reaction is carried out similarly to known methods at temperatures of from 50 to 250 C. and preferably from about 160 C. to about 220 C. and a pressure from ambient to about 2,000 psi (1.379 ⁇ 10 6 Pa).
- the lactide or glycolide can be polymerized separately, which generally is the preferred case, or together in any ratio or in conjunction with up to about 20 weight percent of another co-polymerizable monomer, such as epsilon-caprolactone, delta-valerolactone, 1,5-dioxepan-2-one, 1,4-dioxan-2-one, beta-butyrolactone and beta-propiolactone or mixtures thereof.
- another co-polymerizable monomer such as epsilon-caprolactone, delta-valerolactone, 1,5-dioxepan-2-one, 1,4-dioxan-2-one, beta-butyrolactone and beta-propiolactone or mixtures thereof.
- lactone comonomers have the one of the structional formulas selected from the group consisting of ##STR1## wherein n is 4 or 5, h, i, k and m are independently one or two and each R is independently chosen from H or hydrocarbyl containing up to 12 carbon atoms.
- Polymerization methods include methods carried out in a melt, in solution, or in suspension.
- tin catalysts are used for the polymerization reaction, and stannous octoate (stannous 2-ethylhexanoate).
- stannous octoate stannous 2-ethylhexanoate
- Other tin compounds having a catalytic effect on the polymerization reaction may also be used, such as tetraphenyltin, tin bis-acetylacetonate, and tin (II) chloride.
- Suitable catalysts also include yttrium and lanthanum rare earth series metals having atomic numbers 57 through 71, namely lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium.
- Preferred metals are yttrium, lanthanum, erbium, samarium and dysprosium.
- yttrium, lanthanum and mixtures of yttrium and rare earth metals that are obtained from the mining and smelting of rare earth metal ores.
- the yttrium and rare earth metal is trivalent.
- the catalyst should preferably be at least slightly soluble in the reaction medium.
- Additional ring opening catalysts suitable for use herein include titanates, zirconates, diethyl zinc, and antimony oxides and halides.
- polymer includes homopolymers as well as copolymers; the term “copolymers” includes bipolymers, tripolymers and higher multipolymers; and the term “monomer/catalyst ratio” includes all of the polymerizable and copolymerizable monomeric species present in the reaction system including cyclic esters and comonomers, if any.
- the monomer to catalyst ratio is generally maintained below 20,000:1 by moles, and it is usually not less than 500:1. Good results have been observed when the monomer/catalyst ratio is within the range of 15,000 to 1,000 to 1 by moles, with the preferred ratio being in the range of from 10,000 to 4,000 to 1 by moles.
- monomer to catalyst ratios less than 500:1 are used, product coloration, contamination and instability can result.
- the polymerization can be carried out in any standard equipment. Continuous polymerization can be effected in a screw extruder, or any other reactor with adequate mixing to give a highly homogeneous product.
- a stirred tank can be used for batch polymerization, and also for continuous feed of monomer and removal of polymer (or intermediate product).
- the polymerization can be carried out in the presence or absence of a solvent.
- a preferred technique is to operate in the bulk (i.e., without solvent) and to prepare an intermediate in a stirred tank, with final polymerization being carried out in a screw extruder.
- the catalyst can be added to the monomer before or in the initial reactor.
- a 9:1 mixture of L- and D/L-lactide (with water and lactic acid undetectable by GC analysis) was fed as a solid to a twin screw extruder (with barrel diameter 30 mm) held at 180 C. at a rate of 15 pounds/hour.
- a 0.5 molar azeotropically dried toluene solution of stannous octoate was added to the monomer stream prior to melting at a rate to give a molar monomer to catalyst ratio of 6000/1.
- the residence time was estimated via color pellet injection to be ca. 5 min.
- the polymer strand exiting the extruder was quenched to room temperature and pelletized. TGA analysis of the resulting pellet indicated a conversion of 98%.
- the product could be processed via methods known in the art into oriented films, injection molded parts of complex shape, monofilaments and microcellular foams.
- FIG. 1 shows the negative effect of added organic acid on the polymerization rate.
Abstract
Description
TABLE 1 ______________________________________ Mon/Cat Polym. Polym. Percent (mol ratio) Time(h) Temp (C.) Reaction Reference ______________________________________ 10000:1 24 130 44 (1) 3333 25 130 96 (1) 20000 14 180 78 (1) 20000 24 150 64 (1) 10000 4 180 93 (1) 18842 1.4 200 96 (2) 18842 2.5 180 96 (2) 18842 1 160 71 (2) 10000 2 160 91 (3) 10000 0.35 180 57 (3) 10000 0.48 180 78 (3) ______________________________________ (1) DAHLMANN, J.; RAFLER, G; FECHNER, K; MEHLIS, B. British Polymer Journal, 1990, 23, 235-240. (2) PENNINGS, A. J; LEENSLAG, J. Makromol Chem, 1987, 188, 1809-1814. (3) JAMSHIDI, K.; EBERHART, R.C.; HYON S.H.; IKADA. Y; Polymer preprints 1987, 28 236-237 Mon/Cat = Monomer/Catalyst Ratio Polym = Polymerization
Claims (8)
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/057,817 US5310599A (en) | 1993-05-06 | 1993-05-06 | Method for making polymers of alpha-hydroxy acids |
EP94303291A EP0627453B1 (en) | 1993-05-06 | 1994-05-06 | Method for making polymers of alpha-hydroxy acids |
DE69408366T DE69408366T2 (en) | 1993-05-06 | 1994-05-06 | Process for the preparation of polymers from alpha-hydroxycarboxylic acids |
JP6094507A JPH07126358A (en) | 1993-05-06 | 1994-05-06 | Preparation of polymer of alpha hydroxy acid |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/057,817 US5310599A (en) | 1993-05-06 | 1993-05-06 | Method for making polymers of alpha-hydroxy acids |
Publications (1)
Publication Number | Publication Date |
---|---|
US5310599A true US5310599A (en) | 1994-05-10 |
Family
ID=22012932
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/057,817 Expired - Lifetime US5310599A (en) | 1993-05-06 | 1993-05-06 | Method for making polymers of alpha-hydroxy acids |
Country Status (4)
Country | Link |
---|---|
US (1) | US5310599A (en) |
EP (1) | EP0627453B1 (en) |
JP (1) | JPH07126358A (en) |
DE (1) | DE69408366T2 (en) |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5457144A (en) * | 1992-03-06 | 1995-10-10 | Rohm And Haas Company | Degradable polyamides |
US5484882A (en) * | 1993-07-12 | 1996-01-16 | Dainippon Ink And Chemicals, Inc. | Process for the continuous production of biodegradable polyester polymer |
US5521278A (en) * | 1994-08-18 | 1996-05-28 | Ecological Chemical Products | Integrated process for the manufacture of lactide |
WO1996031494A1 (en) * | 1995-04-05 | 1996-10-10 | Chronopol, Inc. | Method to produce and purify cyclic esters |
US5675021A (en) * | 1992-03-19 | 1997-10-07 | Chronopol, Inc. | Method to produce and purify cyclic esters |
WO1997041165A1 (en) * | 1996-04-26 | 1997-11-06 | Michigan State University | Bulk reactive extrusion polymerization process producing aliphatic ester polymer compositions |
US5750732A (en) * | 1992-03-19 | 1998-05-12 | Chronopol, Inc. | Method to produce cyclic esters |
US6083524A (en) | 1996-09-23 | 2000-07-04 | Focal, Inc. | Polymerizable biodegradable polymers including carbonate or dioxanone linkages |
KR100503890B1 (en) * | 2002-10-08 | 2005-07-26 | 한국과학기술연구원 | Biodegradable polyester polymer and method for preparing the same using compressed gases |
US20090291607A1 (en) * | 2006-07-14 | 2009-11-26 | Wang James H | Biodegradable aliphatic-aromatic copolyester for use in nonwoven webs |
US20090311937A1 (en) * | 2006-07-14 | 2009-12-17 | Kimberly-Clark Worldwide, Inc. | Biodegradable polylactic acid for use in nonwoven webs |
US20100048082A1 (en) * | 2006-12-15 | 2010-02-25 | Topolkaraev Vasily A | Biodegradable polylactic acids for use in forming fibers |
US20100048081A1 (en) * | 2006-12-15 | 2010-02-25 | Topolkaraev Vasily A | Biodegradable polyesters for use in forming fibers |
US20100323575A1 (en) * | 2007-12-13 | 2010-12-23 | Aimin He | Biodegradable fibers formed from a thermoplastic composition containing polylactic acid and a polyether copolymer |
US20110059669A1 (en) * | 2007-08-22 | 2011-03-10 | Aimin He | Multicomponent biodegradable filaments and nonwoven webs formed therefrom |
US20110065573A1 (en) * | 2008-05-30 | 2011-03-17 | Mceneany Ryan J | Polylactic acid fibers |
US20110140307A1 (en) * | 2008-09-01 | 2011-06-16 | Nanjing University Of Technology | Method of making polylactic acid and its products |
US8461262B2 (en) | 2010-12-07 | 2013-06-11 | Kimberly-Clark Worldwide, Inc. | Polylactic acid fibers |
WO2013119959A1 (en) * | 2012-02-09 | 2013-08-15 | Novus International Inc. | Heteroatom containing cyclic dimers |
US8609808B2 (en) | 2006-07-14 | 2013-12-17 | Kimberly-Clark Worldwide, Inc. | Biodegradable aliphatic polyester for use in nonwoven webs |
US9080013B2 (en) | 2013-07-22 | 2015-07-14 | Kureha Corporation | Production method for aliphatic polyester |
US9452143B2 (en) | 2012-07-12 | 2016-09-27 | Novus International, Inc. | Matrix and layer compositions for protection of bioactives |
US10266512B2 (en) | 2017-08-10 | 2019-04-23 | Novus International, Inc. | Processes for preparing heteroatom containing cyclic dimers |
US10584306B2 (en) | 2017-08-11 | 2020-03-10 | Board Of Regents Of The University Of Oklahoma | Surfactant microemulsions |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
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DE10113302B4 (en) * | 2001-03-19 | 2009-09-24 | Fraunhofer-Gesellschaft für die angewandte Forschung e.V. | Process for the preparation of homo- and copolyesters of lactic acid |
JP2003105073A (en) * | 2001-09-27 | 2003-04-09 | Asahi Kasei Corp | Production method for aliphatic polyester |
US7557157B2 (en) | 2004-11-09 | 2009-07-07 | E. I. Du Pont De Nemours And Company | Polymerization of macrocyclic polyester oligomers at elevated temperature using rare earth element catalysts |
CN101374883B (en) | 2006-01-30 | 2011-06-29 | 株式会社吴羽 | Process for producing aliphatic polyester |
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US4033938A (en) * | 1974-01-21 | 1977-07-05 | American Cyanamid Company | Polymers of unsymmetrically substituted 1,4-dioxane-2,5-diones |
US4622244A (en) * | 1979-09-04 | 1986-11-11 | The Washington University | Process for preparation of microcapsules |
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US5028667A (en) * | 1989-09-29 | 1991-07-02 | E.I. Du Pont De Nemours And Company | Yttrium and rare earth compounds catalyzed lactone polymerization |
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EP0372221B1 (en) * | 1988-11-01 | 2000-01-19 | Boehringer Ingelheim Pharma KG | Continuous process for the preparation of resorbable polyesters, and their use |
DE3936188A1 (en) * | 1988-11-01 | 1990-05-03 | Boehringer Ingelheim Kg | Continuous prodn. of bio:absorbable polyester(s) - by polymerisation in temp.-controlled extruder |
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-
1993
- 1993-05-06 US US08/057,817 patent/US5310599A/en not_active Expired - Lifetime
-
1994
- 1994-05-06 DE DE69408366T patent/DE69408366T2/en not_active Expired - Fee Related
- 1994-05-06 EP EP94303291A patent/EP0627453B1/en not_active Expired - Lifetime
- 1994-05-06 JP JP6094507A patent/JPH07126358A/en active Pending
Patent Citations (8)
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Cited By (42)
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---|---|---|---|---|
US5457144A (en) * | 1992-03-06 | 1995-10-10 | Rohm And Haas Company | Degradable polyamides |
US5675021A (en) * | 1992-03-19 | 1997-10-07 | Chronopol, Inc. | Method to produce and purify cyclic esters |
US5750732A (en) * | 1992-03-19 | 1998-05-12 | Chronopol, Inc. | Method to produce cyclic esters |
US5856523A (en) * | 1992-03-19 | 1999-01-05 | Chronopol, Inc. | Purifying cyclic esters by aqueous solvent extraction and further purification |
US5484882A (en) * | 1993-07-12 | 1996-01-16 | Dainippon Ink And Chemicals, Inc. | Process for the continuous production of biodegradable polyester polymer |
US5686630A (en) * | 1993-09-29 | 1997-11-11 | Chronopol, Inc. | Purifying cyclic esters by aqueous solvent extraction |
US5521278A (en) * | 1994-08-18 | 1996-05-28 | Ecological Chemical Products | Integrated process for the manufacture of lactide |
WO1996031494A1 (en) * | 1995-04-05 | 1996-10-10 | Chronopol, Inc. | Method to produce and purify cyclic esters |
WO1997041165A1 (en) * | 1996-04-26 | 1997-11-06 | Michigan State University | Bulk reactive extrusion polymerization process producing aliphatic ester polymer compositions |
US5801224A (en) * | 1996-04-26 | 1998-09-01 | Board Of Trustees Operating Michigan State University | Bulk reactive extrusion polymerization process producing aliphatic ester polymer compositions |
US5906783A (en) * | 1996-04-26 | 1999-05-25 | Board Of Trustees Operating Michigan State University | Bulk reaction extrusion polymerization process producing aliphatic ester polymer compositions |
US5969089A (en) * | 1996-04-26 | 1999-10-19 | Board Of Trustees Operating Michigan State University | Bulk reactive extrusion polymerization process producing aliphatic ester polymer compositions |
US6083524A (en) | 1996-09-23 | 2000-07-04 | Focal, Inc. | Polymerizable biodegradable polymers including carbonate or dioxanone linkages |
US6177095B1 (en) | 1996-09-23 | 2001-01-23 | Focal, Inc | Polymerizable biodegradable polymers including carbonate or dioxanone linkages |
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US20090291607A1 (en) * | 2006-07-14 | 2009-11-26 | Wang James H | Biodegradable aliphatic-aromatic copolyester for use in nonwoven webs |
US20090311937A1 (en) * | 2006-07-14 | 2009-12-17 | Kimberly-Clark Worldwide, Inc. | Biodegradable polylactic acid for use in nonwoven webs |
US9394629B2 (en) | 2006-07-14 | 2016-07-19 | Kimberly-Clark Worldwide, Inc. | Biodegradable aliphatic-aromatic copolyester for use in nonwoven webs |
US8609808B2 (en) | 2006-07-14 | 2013-12-17 | Kimberly-Clark Worldwide, Inc. | Biodegradable aliphatic polyester for use in nonwoven webs |
US9260802B2 (en) | 2006-07-14 | 2016-02-16 | Kimberly-Clark Worldwide, Inc. | Biodegradable aliphatic polyester for use in nonwoven webs |
US9091004B2 (en) | 2006-07-14 | 2015-07-28 | Kimberly-Clark Worldwide, Inc. | Biodegradable polylactic acid for use in nonwoven webs |
US8710172B2 (en) | 2006-07-14 | 2014-04-29 | Kimberly-Clark Worldwide, Inc. | Biodegradable aliphatic-aromatic copolyester for use in nonwoven webs |
US20100048082A1 (en) * | 2006-12-15 | 2010-02-25 | Topolkaraev Vasily A | Biodegradable polylactic acids for use in forming fibers |
US20100048081A1 (en) * | 2006-12-15 | 2010-02-25 | Topolkaraev Vasily A | Biodegradable polyesters for use in forming fibers |
US20110059669A1 (en) * | 2007-08-22 | 2011-03-10 | Aimin He | Multicomponent biodegradable filaments and nonwoven webs formed therefrom |
US8518311B2 (en) | 2007-08-22 | 2013-08-27 | Kimberly-Clark Worldwide, Inc. | Multicomponent biodegradable filaments and nonwoven webs formed therefrom |
US20100323575A1 (en) * | 2007-12-13 | 2010-12-23 | Aimin He | Biodegradable fibers formed from a thermoplastic composition containing polylactic acid and a polyether copolymer |
US20110065573A1 (en) * | 2008-05-30 | 2011-03-17 | Mceneany Ryan J | Polylactic acid fibers |
US8268738B2 (en) | 2008-05-30 | 2012-09-18 | Kimberly-Clark Worldwide, Inc. | Polylactic acid fibers |
US8241545B2 (en) * | 2008-09-01 | 2012-08-14 | Nanjing Universty of Technology | Method of making polylactic acid and its products |
US20110140307A1 (en) * | 2008-09-01 | 2011-06-16 | Nanjing University Of Technology | Method of making polylactic acid and its products |
US8461262B2 (en) | 2010-12-07 | 2013-06-11 | Kimberly-Clark Worldwide, Inc. | Polylactic acid fibers |
US9011832B2 (en) | 2012-02-09 | 2015-04-21 | Novus International, Inc. | Heteroatom containing cyclic dimers |
US9284294B2 (en) | 2012-02-09 | 2016-03-15 | Novus International, Inc. | Functionalized polymer compositions |
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US9447068B2 (en) | 2012-02-09 | 2016-09-20 | Novus International, Inc. | Functionalized polymer compositions |
US10457660B2 (en) | 2012-02-09 | 2019-10-29 | Novus International, Inc. | Heteroatom containing cyclic dimers |
US9452143B2 (en) | 2012-07-12 | 2016-09-27 | Novus International, Inc. | Matrix and layer compositions for protection of bioactives |
US9655863B2 (en) | 2012-07-12 | 2017-05-23 | Novus International, Inc. | Matrix and layer compositions for protection of bioactives |
US9080013B2 (en) | 2013-07-22 | 2015-07-14 | Kureha Corporation | Production method for aliphatic polyester |
US10266512B2 (en) | 2017-08-10 | 2019-04-23 | Novus International, Inc. | Processes for preparing heteroatom containing cyclic dimers |
US10584306B2 (en) | 2017-08-11 | 2020-03-10 | Board Of Regents Of The University Of Oklahoma | Surfactant microemulsions |
Also Published As
Publication number | Publication date |
---|---|
JPH07126358A (en) | 1995-05-16 |
EP0627453A2 (en) | 1994-12-07 |
DE69408366D1 (en) | 1998-03-12 |
DE69408366T2 (en) | 1998-05-20 |
EP0627453A3 (en) | 1995-03-15 |
EP0627453B1 (en) | 1998-02-04 |
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